From 88447c91afb96bffbc1111c6740883cd4509f5ea Mon Sep 17 00:00:00 2001
From: David Greenspan <dgreenspan@alum.mit.edu>
Date: Tue, 1 Jul 2014 13:59:41 -0700
Subject: [PATCH] Shave 10 seconds off test runs with DevTools open
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Chrome’s “async stack traces” feature makes addEventListener a little slower.  DOMBackend’s teardown listeners were causing unnecessary calls to addEventListener in jQuery.  Tell jQuery not to do that.
---
 packages/blaze/dombackend.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/packages/blaze/dombackend.js b/packages/blaze/dombackend.js
index 1198c2a49f..f60e101164 100644
--- a/packages/blaze/dombackend.js
+++ b/packages/blaze/dombackend.js
@@ -110,6 +110,12 @@ DOMBackend.Teardown = {
 };
 
 $jq.event.special[DOMBackend.Teardown._JQUERY_EVENT_NAME] = {
+  setup: function () {
+    // This "setup" callback is important even though it is empty!
+    // Without it, jQuery will call addEventListener, which is a
+    // performance hit, especially with Chrome's async stack trace
+    // feature enabled.
+  },
   teardown: function() {
     var elem = this;
     var callbacks = elem[DOMBackend.Teardown._CB_PROP];